1. Field of the Invention
Embodiments of the invention relate generally to micro-fluidic devices. In particular, the embodiments relate to fabricating structures in micro-fluidic devices based on hydrodynamic focusing.
2. Background Information
Various approaches to fabrication within micro-fluidic devices have been discussed in the patent literature. One example is provided in U.S. Pat. No. 6,488,872 to Beebe et al. (hereinafter referred to as the '872 patent), which is not admitted to be prior art by its inclusion in the background section.
As discussed in the abstract of the '872 patent, in part microfabricated devices and methods of manufacturing the devices are disclosed. The devices are manufactured from a substrate having microscale fluid channels, and polymerizing a polymerizable mixture in the channels to form stimuli-responsive operating components of the device. The operating components can be functional or structural components. The method of manufacture obviates the traditional assembly of microscale components to form a device because the microscale components are formed in situ on or within the device. The '872 patent also discusses using hydrodynamic focusing to continuously manufacture small diameter polymeric beads and threads.
The beads and threads do not contact the channel surfaces and are removed or emerged from the channel.